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From: klee@wsl.dec.com (Ken Lee)
Newsgroups: comp.windows.x
Subject: Re: XSetWindowBackgroundPixmap?
Message-ID: <3063@bacchus.dec.com>
Date: 20 Mar 90 19:27:15 GMT
References: <33267@shemp.CS.UCLA.EDU>
Sender: news@decwrl.dec.com
Reply-To: klee@decwrl.dec.com
Organization: DEC Western Software Laboratory
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In article <33267@shemp.CS.UCLA.EDU>, arman@oahu.cs.ucla.edu (Arman
Bostani) writes:
> If I'm using XSetWindowBackgroundPixmap(dpy, win, pix), is it
> guaranteed that subsequent changes to the pixmap will appear in win,
> whenever XClearWindow(win) is called?

Background pixmaps are not the same as backing store.  Section 3.2.1 of
the Xlib manual says:  "If you later draw into the pixmap used for the
background, what happens is undefined because the X implementation is
free to make a copy of the pixmap or to use the same pixmap."

Ken Lee
DEC Western Software Laboratory, Palo Alto, Calif.
Internet: klee@wsl.dec.com
uucp: uunet!decwrl!klee